In brief:
Several possibilitis

First off you need to see a dentist.

You could have an abscessed tooth. It could be a TMJ problem, or a bite problem. Advance gum and bone disease is another possibility. No matter what is causing the pain, you need to see a dentist and get treatment. Pain tells us that something is wrong and may be affecting your overall health.

In brief:
Several possibilitis

First off you need to see a dentist.

You could have an abscessed tooth. It could be a TMJ problem, or a bite problem. Advance gum and bone disease is another possibility. No matter what is causing the pain, you need to see a dentist and get treatment. Pain tells us that something is wrong and may be affecting your overall health.
Would you like to video or text chat with me?

In brief:
So many problems

Without an examination with radiographs, any answer given is pure speculation.

Since it needs to be examined, and three months is a long time to be in pain, why don't you make an appointment with your dentist so that this problem can be resolved?
Feel better soon.

In brief:
So many problems

Without an examination with radiographs, any answer given is pure speculation.

Since it needs to be examined, and three months is a long time to be in pain, why don't you make an appointment with your dentist so that this problem can be resolved?
Feel better soon.
Would you like to video or text chat with me?